//package com.linkwechat.gateway.filter;
//
//import cn.hutool.core.net.Ipv4Util;
//import cn.hutool.core.util.ObjectUtil;
//import com.alibaba.csp.sentinel.util.StringUtil;
//import com.alibaba.fastjson.JSONObject;
//import com.linkwechat.common.utils.StringUtils;
//import com.linkwechat.common.utils.ip.IpUtils;
//import com.linkwechat.gateway.constant.GatewayLog;
//import lombok.extern.slf4j.Slf4j;
//import org.reactivestreams.Publisher;
//import org.springframework.cloud.gateway.filter.GatewayFilterChain;
//import org.springframework.cloud.gateway.filter.GlobalFilter;
//import org.springframework.cloud.gateway.filter.factory.rewrite.CachedBodyOutputMessage;
//import org.springframework.cloud.gateway.route.Route;
//import org.springframework.cloud.gateway.support.BodyInserterContext;
//import org.springframework.cloud.gateway.support.ServerWebExchangeUtils;
//import org.springframework.core.Ordered;
//import org.springframework.core.io.buffer.DataBuffer;
//import org.springframework.core.io.buffer.DataBufferFactory;
//import org.springframework.core.io.buffer.DataBufferUtils;
//import org.springframework.core.io.buffer.DefaultDataBufferFactory;
//import org.springframework.http.HttpHeaders;
//import org.springframework.http.HttpStatus;
//import org.springframework.http.MediaType;
//import org.springframework.http.codec.HttpMessageReader;
//import org.springframework.http.server.reactive.ServerHttpRequest;
//import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
//import org.springframework.http.server.reactive.ServerHttpResponse;
//import org.springframework.http.server.reactive.ServerHttpResponseDecorator;
//import org.springframework.stereotype.Component;
//import org.springframework.util.MultiValueMap;
//import org.springframework.web.reactive.function.BodyInserter;
//import org.springframework.web.reactive.function.BodyInserters;
//import org.springframework.web.reactive.function.server.HandlerStrategies;
//import org.springframework.web.reactive.function.server.ServerRequest;
//import org.springframework.web.server.ServerWebExchange;
//import org.springframework.web.util.WebUtils;
//import reactor.core.publisher.Flux;
//import reactor.core.publisher.Mono;
//
//import javax.servlet.http.HttpServletRequest;
//import java.nio.charset.StandardCharsets;
//import java.util.Date;
//import java.util.List;
//import java.util.Map;
//
///**
// * 日志过滤器，用于记录日志
// * @author danmo
// * @date 2023年03月10日 18:50
// */
//@Slf4j
//@Component
//public class AccessLogFilter implements GlobalFilter, Ordered {
//
//    private final List<HttpMessageReader<?>> messageReaders = HandlerStrategies.withDefaults().messageReaders();
//
//    @Override
//    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
//        ServerHttpRequest request = exchange.getRequest();
//
//        // 请求路径
//        String requestPath = request.getPath().pathWithinApplication().value();
//
//        //这是个神奇的地方
//        if(ObjectUtil.equal("/auth/accountLogin",requestPath)){
//            return chain.filter(exchange);
//        }
//
//        Route route = getGatewayRoute(exchange);
//
//        String ipAddress = IpUtils.getIpAddr(request);
//
//        GatewayLog gatewayLog = new GatewayLog();
//        gatewayLog.setSchema(request.getURI().getScheme());
//        gatewayLog.setRequestMethod(request.getMethodValue());
//        gatewayLog.setRequestPath(requestPath);
//        gatewayLog.setTargetServer(route.getId());
//        gatewayLog.setRequestTime(new Date());
//        gatewayLog.setIp(ipAddress);
//
//        MediaType mediaType = request.getHeaders().getContentType();
//
//        if(MediaType.APPLICATION_FORM_URLENCODED.isCompatibleWith(mediaType) || MediaType.APPLICATION_JSON.isCompatibleWith(mediaType)){
//            return writeBodyLog(exchange, chain, gatewayLog);
//        }else{
//            return writeBasicLog(exchange, chain, gatewayLog);
//        }
//    }
//
//    private Mono<Void> writeBasicLog(ServerWebExchange exchange, GatewayFilterChain chain, GatewayLog accessLog) {
//        //StringBuilder builder = new StringBuilder();
//        MultiValueMap<String, String> queryParams = exchange.getRequest().getQueryParams();
//        /*for (Map.Entry<String, List<String>> entry : queryParams.entrySet()) {
//            builder.append(entry.getKey()).append("=").append(StringUtils.join(entry.getValue(), ","));
//        }*/
//        accessLog.setRequestBody(JSONObject.toJSONString(queryParams));
//
//        //获取响应体
//        ServerHttpResponseDecorator decoratedResponse = recordResponseLog(exchange, accessLog);
//
//        return chain.filter(exchange.mutate().response(decoratedResponse).build())
//                .then(Mono.fromRunnable(() -> {
//                    // 打印日志
//                    writeAccessLog(accessLog);
//                }));
//    }
//
//
//    private Mono writeBodyLog(ServerWebExchange exchange, GatewayFilterChain chain, GatewayLog gatewayLog) {
//        ServerRequest serverRequest = ServerRequest.create(exchange,messageReaders);
//
//        Mono<JSONObject> modifiedBody = serverRequest.bodyToMono(JSONObject.class)
//                .flatMap(body ->{
//                    gatewayLog.setRequestBody(body.toJSONString());
//                    return Mono.just(body);
//                });
//
//        // 通过 BodyInserter 插入 body(支持修改body), 避免 request body 只能获取一次
//        BodyInserter bodyInserter = BodyInserters.fromPublisher(modifiedBody, JSONObject.class);
//        HttpHeaders headers = new HttpHeaders();
//        headers.putAll(exchange.getRequest().getHeaders());
//        // the new content type will be computed by bodyInserter
//        // and then set in the request decorator
//        headers.remove(HttpHeaders.CONTENT_LENGTH);
//
//        CachedBodyOutputMessage outputMessage = new CachedBodyOutputMessage(exchange, headers);
//
//        return bodyInserter.insert(outputMessage,new BodyInserterContext())
//                .then(Mono.defer(() -> {
//                    // 重新封装请求
//                    ServerHttpRequest decoratedRequest = requestDecorate(exchange, headers, outputMessage);
//
//                    // 记录响应日志
//                    ServerHttpResponseDecorator decoratedResponse = recordResponseLog(exchange, gatewayLog);
//
//                    // 记录普通的
//                    return chain.filter(exchange.mutate().request(decoratedRequest).response(decoratedResponse).build())
//                            .then(Mono.fromRunnable(() -> {
//                                // 打印日志
//                                writeAccessLog(gatewayLog);
//                            }));
//                }));
//    }
//
//    /**
//     * 打印日志
//     * @date 2023/3/16 14:53
//     * @param gatewayLog 网关日志
//     */
//    private void writeAccessLog(GatewayLog gatewayLog) {
//        log.info("请求日志：INFO:{}",JSONObject.toJSONString(gatewayLog));
//    }
//
//
//
//    private Route getGatewayRoute(ServerWebExchange exchange) {
//        return exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_ROUTE_ATTR);
//    }
//
//
//    /**
//     * 请求装饰器，重新计算 headers
//     * @param exchange
//     * @param headers
//     * @param outputMessage
//     * @return
//     */
//    private ServerHttpRequestDecorator requestDecorate(ServerWebExchange exchange, HttpHeaders headers,
//                                                       CachedBodyOutputMessage outputMessage) {
//        return new ServerHttpRequestDecorator(exchange.getRequest()) {
//            @Override
//            public HttpHeaders getHeaders() {
//                long contentLength = headers.getContentLength();
//                HttpHeaders httpHeaders = new HttpHeaders();
//                httpHeaders.putAll(super.getHeaders());
//                if (contentLength > 0) {
//                    httpHeaders.setContentLength(contentLength);
//                } else {
//                    // TODO: this causes a 'HTTP/1.1 411 Length Required' // on
//                    // httpbin.org
//                    httpHeaders.set(HttpHeaders.TRANSFER_ENCODING, "chunked");
//                }
//                return httpHeaders;
//            }
//
//            @Override
//            public Flux<DataBuffer> getBody() {
//                return outputMessage.getBody();
//            }
//        };
//    }
//
//
//    /**
//     * 记录响应日志
//     * 通过 DataBufferFactory 解决响应体分段传输问题。
//     */
//    private ServerHttpResponseDecorator recordResponseLog(ServerWebExchange exchange, GatewayLog gatewayLog) {
//        ServerHttpResponse response = exchange.getResponse();
//        DataBufferFactory bufferFactory = response.bufferFactory();
//
//        return new ServerHttpResponseDecorator(response) {
//            @Override
//            public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
//                if (body instanceof Flux) {
//                    Date responseTime = new Date();
//                    gatewayLog.setResponseTime(responseTime);
//                    // 计算执行时间
//                    long executeTime = (responseTime.getTime() - gatewayLog.getRequestTime().getTime());
//
//                    gatewayLog.setExecuteTime(executeTime);
//
//                    // 获取响应类型，如果是 json 就打印
//                    String originalResponseContentType = exchange.getAttribute(ServerWebExchangeUtils.ORIGINAL_RESPONSE_CONTENT_TYPE_ATTR);
//
//
//                    if (ObjectUtil.equal(this.getStatusCode(), HttpStatus.OK)
//                            && StringUtil.isNotBlank(originalResponseContentType)
//                            && originalResponseContentType.contains("application/json")) {
//
//                        Flux<? extends DataBuffer> fluxBody = Flux.from(body);
//                        return super.writeWith(fluxBody.buffer().map(dataBuffers -> {
//
//                            // 合并多个流集合，解决返回体分段传输
//                            DataBufferFactory dataBufferFactory = new DefaultDataBufferFactory();
//                            DataBuffer join = dataBufferFactory.join(dataBuffers);
//                            byte[] content = new byte[join.readableByteCount()];
//                            join.read(content);
//
//                            // 释放掉内存
//                            DataBufferUtils.release(join);
//                            String responseResult = new String(content, StandardCharsets.UTF_8);
//
//
//
//                            gatewayLog.setResponseData(responseResult);
//
//                            return bufferFactory.wrap(content);
//                        }));
//                    }
//                }
//                // if body is not a flux. never got there.
//                return super.writeWith(body);
//            }
//        };
//    }
//
//
//    @Override
//    public int getOrder() {
//        return -100;
//    }
//}
